{
  "bibcode": "2022GCN.31779....1G",
  "body": "R. Gopalakrishnan (IUCAA), V. Prasad (IUCAA), A. Suresh (IITB), G.\nWaratkar (IITB), A. Vibhute (IUCAA), V. Bhalerao (IITB), D. Bhattacharya\n(IUCAA), A. R. Rao (IUCAA/TIFR), and S. Vadawale (PRL) report on behalf\nof the AstroSat CZTI collaboration:\n\nAnalysis of AstroSat CZTI data with the ML pipeline (Abraham et al.,\n2021, MNRAS, 504, 3084) and the CIFT framework (Sharma et al., 2021,\nJApA, 42, 73) showed detection of a bright long GRB 220320A which was\nalso detected by IPN (contributed by Konus-Wind at GCN Notices), and\nFermi - GBM (Trigger - 669443999).\n\nThe source was clearly detected in the 20-200 keV energy range. The\nlight curve peaks at 2022-03-20 04:39:59.25 UT. The measured peak count\nrate associated with the burst is 2398 (+336, -71) counts/s above the\nbackground in the combined data of four quadrants, with a total of 5427\n(+307, -331) counts. The local mean background count rate was 507 (+5,\n-9) counts/s. Using cumulative rates, we measure a T90 of 11 (+1, -1) s.\n\nIt was also clearly detected in the CsI anticoincidence (Veto) detector\nin the 100-500 keV energy range. The light curve showed a peak at\n2022-03-20 04:39:59.13 UT. The measured peak count rate is 3438 (+112,\n-122) counts/s  above the background in the combined Veto data of four\nquadrants, with a total of 10543 (+502, -570) counts. The local mean\nbackground count rate was 1529 (+5, -5) counts/s. We measure a T90 of 16\n(+3, -3) s from the cumulative Veto light curve.\n\nCZTI GRB detections are reported regularly on the payload site at\nhttp://astrosat.iucaa.in/czti/?q=grb [1]. CZTI is built by a TIFR-led\nconsortium of institutes across India, including VSSC, ISAC, IUCAA, SAC,\nand PRL. The Indian Space Research Organisation funded, managed, and\nfacilitated the project. \n\nLinks:\n------\n[1] http://astrosat.iucaa.in/czti/?q=grb",
  "circularId": 31779,
  "createdOn": 1647934612000,
  "email": "gauravwaratkar@iitb.ac.in",
  "subject": "GRB 220320A: AstroSat CZTI detection",
  "submitter": "Gaurav Waratkar at IIT,Bombay  <gauravwaratkar@iitb.ac.in>",
  "eventId": "GRB 220320A"
}